One thematic encyclopedia deals with all the issues which are kind of (compatibly, or implicitly) related to the subject. Therefore, it does not just take the words of a text into consideration, but goes beyond and provides a much broadercontext of information and resources. The purpose of setting such encyclopedias is to guide those who refer to it to all the Qur’anic verses related to each of topics and concepts, weather these concepts are derived from the specific terms or are a combination of words and themes of the Qur’anic Verses. In the present article, adopting a descriptive approach,the author intends to study four thematic encyclopedias of the Qur’an. These encyclopedias include: Tafsīl al-Āyāt by Jul Labum; Tabaqāt al-Āyāt by Khalil Sabry; Thematic Encyclopedia of the Qur’an by KāmrānFāni and BahāoddinKhorramshāhi; and Encyclopedia of the Qur’an by Hāshemi-e Rafsanjāni. As an introduction to the paper, she is firstly going to talk about the literal and technical meanings of encyclopedia, different kinds of encyclopedias of the Qur’an, the purpose of their setting, and the difference between thematic exegesis and thematic encyclopedia. Following this, in order to give a report of each one of these four encyclopedias, she provides a short biography of their authors, and then mentions the books’ features and defects along with some tips on how to use them.